My Solution of Prob. 4.8 - 4.10

[jehannn]

Hi Steve and pals,

Here is my solution of Prob. 4.8 - 4.10 , please check it.

If there is any wrong, please let me know, thanks!!   

Code: (Objective-C)

// Prob 4-8, 4-9, 4-10
// Advance Calculator of Ex 4-6

#import <Foundation/Foundation.h>


@interface Calculator : NSObject
{
	double accumulator;
	double memory;
}

// accumulator methods

-(void) setAccumulator: (double) value;
-(double) clear;
-(double) getAccumulator;

// arithmetic methods

-(double) add: (double) value;
-(double) substract: (double) value;
-(double) multiply: (double) value;
-(double) divide: (double) value;
-(double) changeSign; // change sign of accumulator
-(double) reciprocal; // 1 / accumulator
-(double) xSquared; // accumulator squared

// memory methods

-(double) memoryClear; // clear memory
-(double) memoryStore; // set memory to accumulator
-(double) memoryRecall; // set accumulator to memory
-(double) memoryAdd; // add accumulator to memory
-(double) memorySubstract; // substract accumulator from memory


@end

@implementation Calculator

// accumulator methods

-(void) setAccumulator: (double) value
{
	accumulator = value;
}

-(double) clear;
{
	return accumulator = 0;
}

-(double) getAccumulator;
{
	return accumulator;
}

// arithmetic methods

-(double) add: (double) value;
{
	return accumulator += value;
}

-(double) substract: (double) value;
{
	return accumulator -= value;
}

-(double) multiply: (double) value;
{
	return accumulator *= value;
}

-(double) divide: (double) value;
{
	return accumulator /= value;
}

-(double) changeSign; // change sign of accumulator
{
	return accumulator = -accumulator;
}

-(double) reciprocal; // 1 / accumulator
{
	return accumulator = 1 / accumulator;
}

-(double) xSquared; // accumulator squared
{
	return accumulator *= accumulator;
}


// memory methods

-(double) memoryClear; // clear memory
{
	return memory = 0;
}

-(double) memoryStore; // set memory to accumulator
{
	memory = accumulator;
	return accumulator;
}

-(double) memoryRecall; // set accumulator to memory
{
	return accumulator = memory;
}

-(double) memoryAdd; // add accumulator to memory
{
	return accumulator += memory;
}

-(double) memorySubstract; // substract accumulator from memory
{
	return accumulator -= memory;
}

@end


int main (int argc, const char * argv[]) {
    NSAutoreleasePool * pool = [[NSAutoreleasePool alloc] init];
	
	Calculator *deskCalcu = [[Calculator alloc] init];
	
	[deskCalcu clear];
	[deskCalcu setAccumulator: 5.0];
	NSLog(@"Accumulator = %g",[deskCalcu getAccumulator]);
	NSLog(@"+ 45, accumulator = %g",[deskCalcu add: 45.0]);
	NSLog(@"/ 5, accumulator = %g",[deskCalcu divide: 5.0]);
	NSLog(@"- 5, accumulator = %g",[deskCalcu substract: 5.0]);
	NSLog(@"* 2, accumulator = %g",[deskCalcu multiply: 2.0]);
	NSLog(@"Change sing on accumulator = %g",[deskCalcu changeSign]);
	NSLog(@"Reciprocal of accumulator = %g",[deskCalcu reciprocal]);
	NSLog(@"Squared of accumulator = %g",[deskCalcu xSquared]);
	NSLog(@"Store accumulator to memory, memory = %g", [deskCalcu memoryStore]);
	NSLog(@"Reset accumulator, accumulator = %g", [deskCalcu clear]);
	NSLog(@"+ 20, accumulator = %g",[deskCalcu add: 20.0]);
	NSLog(@"/ 3, accumulator = %g",[deskCalcu divide: 3.0]);
	NSLog(@"- 8, accumulator = %g",[deskCalcu substract: 8.0]);
	NSLog(@"* 4, accumulator = %g",[deskCalcu multiply: 4.0]);
	NSLog(@"Add accumulator to memory, accumulator = %g", [deskCalcu memoryAdd]);
	NSLog(@"Store accumulator to memory, memory = %g", [deskCalcu memoryStore]);
	NSLog(@"Reset accumulator, accumulator = %g", [deskCalcu clear]);
	NSLog(@"+ 7, accumulator = %g",[deskCalcu add: 7.0]);
	NSLog(@"/ 10, accumulator = %g",[deskCalcu divide: 10.0]);
	NSLog(@"Substract memory from accumulator, accumulator = %g", [deskCalcu memorySubstract]);	
	NSLog(@"Store accumulator to memory, memory = %g", [deskCalcu memoryStore]);
	NSLog(@"Reset accumulator, accumulator = %g", [deskCalcu clear]);
	NSLog(@"Recall memory to accumulator, accumulator = %g", [deskCalcu memoryRecall]);
	
	[deskCalcu release];
	[pool release];
    return 0;
}